The invention relates to a device for administering an injectable product in doses, comprising a dosing means which can be restored or reset in accordance with a selected product dosage to be administered.
In known injection devices, for example comprising spindle drives or toothed rack drives, restoring or resetting the dosing means is either very awkward or not possible at all for a user of the device. Restoring can for example make exchanging an emptied product container easier, as is described in EP 0 614 386 B1. To this end, a toothed rack which acts on a piston arranged in the container is only provided with teeth over a portion of its perimeter. The teeth of the toothed rack cooperate with opposing teeth in such a way that it is possible to slide the toothed rack in discrete increments, for the purpose of delivering product, but the toothed rack is prevented from simply retracting. In order to restore the toothed rack, it is formed such that the teeth and the opposing teeth can be disengaged by rotating the toothed rack by 90° and the toothed rack can then be manually retracted and moved to a starting position for another dosed delivery. Restoring the driven member requires a user to perform a number of movements in coordination. When administering medically active products, a preferred use or area of application for the invention, this may be particularly difficult for users who may be suffering from fine motor disorders.